Collision to each other help

Is it possible to have

collisition coll_world, Objects, 2,2
collisition objects, coll_world, 2,2

entitytype myobj,objects
entitytype world,coll_world

?

Yes it is, but you would need to put at the top of your coding:
objects = 1
coll_world = 2
this gives the entities the type number they require for the command entitytype.
then it should work.

You should probably declare those values as constants (ie. Const objects=1) since you won't be changing them.